Helmets



Get. 21, 1969 J, o, LOBELLE 3,473,166

HELMETS Filed Jan. 29, 1968 3 Sheets-Sheet 1 l/VVE/VTOR f7 2 M43661..10455 00/40 1095a 5, 05654850 j- B ERIC NOEL M0888 PAUL DERRICK LEONARD4 051. CHARLES HJ/PHER,

EXECUTOAS T B i 15W, flaw m Mk I Attorney;

Oct. 21, 1969 M. J. o. LOBELLE 3,473,166

HELMETS Filed Jan. 29, 1968 3 Sheets-Sheet 5 52 r mnnnnwggkg 19 "I72'52756 /& 49

fly ER/C' NOEL M0555 PAUL ficAR/C'K LEONARD N064 CHARLES HYPHER,

EXECUTORS Attorney 5 United States Patent 0 HELMETS Marcel Jules OdilonLobelle, deceased, late of Slough, England, by Eric Noel Mobhs, Slough,Paul Derrick Leonard, Farnham Common, and Noel Charles Hypher, Slough,England, executors, assignors to M. L. Aviation Company Limited, Slough,England, a British company Filed Jan. 29, 1968, Ser. No. 703,231 Int.Cl. A421) 3/00 US. Cl. 26 7 Claims ABSTRACT OF THE DISCLOSURE A helmetintended particularly to be worn by an airman occupying an aircraftejection seat. The helmet includes a visor pivoted to the helmet shelland capable of pivoting movement between an upper open position and alower closed position in which the visor protects the airmans face. Thehelmet carries a holder for an electrically ignited cartridge. Theincreased pressure resulting from ignition of the cartridge istransmitted to a chamber containing a pressure responsive member. Themember accordingly moves under the influence of the increased pressureand through a visor lowering mechanism automatically lowers the visor tothe lower closed position thus protecting the airmans face.

This invention relates to helmets of the kind which incorporate a visorpivoted to the helmet shell serving to protect the wearers face when inthe lowered position. Helmets of this type are Worn in aircraft havingejection seats to provide protection against the blasts of air to whichthe wearer is subjected on ejection. Very often the visor is of a tintedtransparent material so that when it is in the lowered position, it alsoshields the wearers eyes from the sun. However whether the visor is ofsuch material or not, it is quite likely that it may be in the raisedposition when an emergency requiring immediate ejection occurs. Thewearer may not have the time or opportunity to first lower the visorbefore initiating the ejection, or he may even be unconscious.

British Patent No. 951,817 and my copending US. patent application Ser.No. 592,166 now Patent No. 3,383,706 describe and claim helmets of thiskind in which the visor is lowered automatically in the event ofejection under the effect of the G-force which the wearer experiences.No action on the part of the wearer is required and his face isprotected almost immediately once he is subjected to a predeterminedG-force for instance 10 to 12 G. While the visor therefore provides thenecessary protection, it is however lowered after the wearer has startedto accelerate upwards and under certain circumstances it may bedesirable that it should be lowered slightly earlier.

According to the present invention, a helmet of the kind firstdiscussed, that is to say incorporating a visor pivoted to the helmetshell serving to protect the wearers face when in the lowered position,includes a holder for an electrically ignited cartridge, a chamber inwhich the pressure rises as a result of ignition of a cartridge in theholder, and a pressure responsive member located within the chamber andconnected through mechanism to the visor. On ignition of a cartridge theresultant pressure increase in the chamber causes the pressureresponsive member to move with the result that the visor is lowered.This occurs a very short period after the cartridge is ignited and henceon ejection from an aircraft for example, if the cartridge is ignited atthe correct instant, the visor reaches the lowered position well beforethe wearers head emerges from the aircraft. Conveniently cartridgeignition is controlled by the same 3,473,166 Patented Oct. 21, 1969 ICC?handle or switch which sets the seat ejection mechanism in operation sothat only a single action on the part of the wearer is required,lowering of the visor and ejection subsequently taking placesequentially.

It can hence be seen that while in the helmets described in our patentand patent application previously mentioned, the visor is lowered as aresult of the movement of the wearer on ejection, in helmets inaccordance with the present invention the visor is lowered on receipt ofan electrical signal. Accordingly such helmets may be worn in othersituations besides flying. When used for flying, although in mostinstances this electrical signal will be produced only when ejection isabout to take place, it may of course be produced on other occassionswhen it is necessary that the visor should be automatically lowered toprotect the wearers face at short notice.

Preferably the holder is designed to hold a pair of cartridges adjacentone another so as to provide a safeguard against a cartridge which failsto ignite. The heat of the adjacent ignited cartridge is in generalsufficient to ignite the faulty cartridge. The cartridges themselves arenormally of the solid fuel type and are sometimes known by other namessuch as for instance gas pressure actuators or initiators.

Particularly if the visor is also to serve as a shield against the sun,it is important that it should be possible for the wearer to raise andlower it manually. Conveniently therefore the visor lowering mechanismincludes a lost-motion connection to permit this.

It is also important that the visor should remain in the loweredposition at least until the emergency is over. However due to leakage itis almost certain that the pressure in the chamber will fall and henceit is quite possible that if worn during ejection, the high blasts ofair which strike the visor may tend to raise it slightly. This isundesirable giving rise to discomfort and possible injury to the wearer.Preferably therefore the visor has side pieces pivoted to the helmetshell in such a way that when in the lowered position the visor can bemoved forwardly away from and rearwardly into contact with the shell.The helmet includes parts which cooperate to prevent the visor beingraised when in contact with the shell in which position a spring biassesthe visor forwardly. In this helmet, movement of the pressure responsivemember to lower the visor subsequently has the effect of drawing thevisor rearwardly, that is to say retracting it against the shell. Inother words to raise the visor, it is necessary to first move itforwardly out of contact with the shell. Any small fall in pressure inthe chamber may allow it to move slightly in a forward direction but itis unlikely to be suflicient to allow the visor to move to the forwardposition in which the parts move out of cooperation with one another.Hence the visor remains efiectively locked in the lowered position. =Itwill be understood that an air blast acts rearwardly on the visor andeven an upward component will not cause the visor to move forwardly. Incontrast the effect of an upword component in the air blast on a helmetnot possessing the features just specified is to cause the visor to riseslightly, the amount depending upon the pressure in the chamber.

Once the emergency is over the wearer may wish to raise the visor.Although in time the pressure in the chamber will fall due to naturalleakage, the construction may be such that an appreciable period elapsesbe fore the wearer can pull the visor forward far enough to subsequentlyraise it. Preferably therefore the helmet includes a lever controllingmechanism which draws the visor forwardly out of contact with the shell.The provision of such mechanism enables the wearer to easily overcomethe effect of the increased pressure in the chamber.

By way of example a flying helmet in accordance with the invention willnow be described in more detail with reference to the accompanyingdrawings, in which:

FIGURE 1 is a side elevation of the helmet with the visor in the loweredposition which it assumes when lowcred manually;

FIGURE 2 is a rear elevation of the helmet, the lower part of which isshown cut away;

FIGURE 3 is a detail view partly in section of the cartridge holdercarried by the helmet shell;

FIGURE 4 is a side elevation corresponding to FIG- URE 1 but showing thevisor in the raised position; and

FIGURE 5 is a side elevation corresponding to FIG- URES 1 and 4 but to alarger scale and partly in section showing the visor lowering mechanismwhich is incorporated in the helmet.

Reference should first be made to FIGURE 1 from which it can be seenthat the helmet, which is of the non-pressurized type, has a shell 1 anda visor 2 of a transparent tinted plastics material carried by a pair ofside pieces one of which is indicated at 3. The helmet includes whatwill be referred to as a jaw piece 4 which extends in front of thewearers jaw and supports an oxygen mask (not shown). The jaw piece 4 ishinged at one side to the helmet shell 1 and at the opposite side acatch (not shown), holds the jaw piece in the closed position asillustrated. Full details of such a jaw piece are given in my copendingBritish patent application No. 9,423/66.

The helmet includes a cartridge holder 5 best seen in FIGURES 2 and 3secured around a pipe 6 which is affixed to the helmet shell by brackets7. The holder 5 holds a pair of cartridges, one of which is visible at 8in FIGURE 3. The cartridge 8 is inserted axially into the holder 5through an aperture 9 into which a plug 10 is subsequently screwed. Theplug contains electrical ignition equipment which ignites the cartridge8 on receipt of an electrical signal received along leads 11. The secondcartridge is inserted through the other end of the holder in anidentical manner and is ignited on receipt of an electrical signalreceived along leads 12. Although not illustrated, the leads 11 and 12are conveniently connected to the electrical control system for theejection seat mechanism. Operation of the ejection handle in addition toinitiating ejection causes electrical signals to pass along the leads 11and 12 thus igniting both cartridges. Duplicate leads, ignitionequipment and cartridges are provided to give increased reliability. Aspreviously indicated if only one cartridge ignites, the heat generatedby it is sufficient to ignite the other cartridge.

The gas produced on ignition passes through an aperture 13 into the pipe6 along which it flows in both directions. As will be described indetail, if the visor is already in the lowered position as illustratedin FIGURE 1, the effect of the gas is to draw it rearwardly so that itsedges contact soft material 14 which lines the face opening on the shell1 and on the jaw piece 4. Accordingly a blast-tight seal is formed sothat the wearers face is protected from air blasts and also from rapidpressure changes when his head subsequently emerges from the aircraft.If the visor is in the raised position illustrated in FIGURE 4, theeffect of the gas is first to lower it to the lowered position shown inFIGURE 1 after which is then drawn rearwardly as just described.

The mechanism which responds to the pressure increase caused by the gasto lower the visor is identical on either side of the helmet andtherefore only that on one side will be described. Referring to FIGURES1 and 4, it can be seen that the visor sidepiece 3 includes an elongatedslot 15 which extends substantially horizontally when the visor is inthe lowered position. An outwardly extending pin 16 secured to the shell1 cooperates with the slot 15 and this arrangement enables the visor tobe moved forwardly and rearwardly when in the lowered position. As shownin FIGURE 1 it is in the forward position in which it does not contactthe soft material 14.

A cover 17 is secured to the shell 1 over the side piece 3 and an arm 18is pivoted to the cover 17 about a bolt 19. The lower end of the arm 18is pivoted to 1 link 20, the other end of which carries a pin 21 whichengages with an arcuate slot 22 in the sidepiece 3. The provision of theslot 22 enables the visor to be raised and lowered manually as required.One end of a piston rod 24 engages with the arm 18. The piston rod ismoved to the right under the influence of the gas produced on ignitionand thereby moves the arm 18 in an anti-clockwise sense moving the link20 to the right. The pin 21 carried by the link 20 therefore rotates thesidepiece 17 in an anti-clockwise sense if the visor is in the raisedposition thus lowering the visor and then drawing it rearwardly. If thevisor is already in the lowered position, it is merely drawn rearwardly.

The lowering mechanism is shown in detail in FIG- URE 5. As shown insolid outline the constituent parts are in the positions they assumewhen the visor is in the raised position. As shown in chain-dottedoutline. they are in positions corresponding to the visor being in thelowered position after manual lowering, while in chain-double-dottedoutline they are in positions corresponding to the visor being in thelowered position after automatic lowering.

The mechanism is best described by considering the visor to be in theraised position. The pressure increase caused by the gas produced onignition of the cartridges is transmitted along the pipe 6 which issecured in a block 25. A number of passages extend horizontally withinthe block and are closed by a plate 26 held in place by bolts 27. Thepressure increase is transmitted to a passage 23 from which a smallpassage 29 extends. This passage 29 serves no functional purpose but isused during manufacture to drill another small passage 30. The passage29 is permanently sealed by a bolt 31. The pressure increase istherefore transmitted along the passage 30 and into what is in effect acylinder 32. The piston rod 24 previously mentioned carries a piston 33which is a sliding fit in the cylinder. Hence it can be seen that whenthe pressure in the cylinder 32 rises, the piston 33 and thus the pistonrod 24 are moved to the right.

The right hand end of the piston rod 24 contacts the arm 18. The partwhich it contacts is a resilient blade 34 secured solely at its lowerend to a pin 35 to which the link 20 is pivoted. The pin 35 serves tojoin two parts 36 and 37 (the part 37 is not shown in FIGURE 5 but onlyin FIGURES 1 and 4) of which the arm 18 is formed. An annular resilientrubber shock absorber 39 is secured by a bolt 40 to a flange 41 on thepart 36 and contacts the blade 34. As the piston rod moves to the rightunder the elfect of the gas a certain amount of energy is dissipated bythe shock absorber 39 thus reducing the speed with which the arm 18 isturned in an anticlockwise sense.

The block 25 has a surface 42 in the shape of an arc of a circleconcentric with the pin 16 when the latter is in the position in theslot 15 shown in FIGURE 5. This surface 42 extends from a substantiallyhorizontal plane upwardly through an angle corresponding to that throughwhich the visor moves when it is raised. The side piece 3 carries a lug43 which cooperates with the surface 42. sliding over the surface as thevisor is raised or lowered and thereby maintaining the visor spaced awayfrom the helmet shell.

The surface 42 terminates just short of the horizontal in a recess 44which is shaped to receive the lug 43. However to do so, a tubularmember 45 has to be moved to the right against a biasing force producedby a compression spring 48. This spring is located within a passage 49in the block 25 and acts on the tubular member 45. The latter has acentral web 46 in which is a slot 47. A pin 57 secured to the shell 1 isa sliding fit in the slot 47 and thereby holds the tubular member 45 inthe passage 49.

As indicated in FIGURE 5, the tubular member 45 is itself recessed atits outer end so that the lug slides over it to the position indicatedas 43. It can be seen that the lug 43' is held within a bracketindicated as 50 secured to the sidepiece 3'.

Manual lowering of the visor causes the pin 21 to slide along thearcuate slot 22. However the length of the slot 22 gives insufiicientlost-motion and hence the arm 18 is pivoted in an anti-clockwise senseto the position indicated as 18.

On cartridge ignition, the arm 18 is pivoted to the position shown as18". If the visor is in the raised position it is first lowered and thenthe turning moment applied to it through the link 20 draws the lug 43inwardly in contact with the tubular member 45 against the eflect of thecompression spring 48. Hence the lug 43 moves under the edge 51 of theblock 25 and thus prevents the visor being raised.

Eventually the pressure in the cylinder 32 falls due to leakage and thewearer is then able to raise the visor. If he wishes to do this earlier,he pivots a lever '52 in a clockwise sense. At this time the lever is inthe position shown in FIGURE 1. As is shown in FIGURE 5, it is pivotedat 53 to a right angled bracket 54 secured at 53 and also by a bolt 55to the bracket 50'. The lever has a cam surface 56 such that when thelever is pivoted in a clockwise sense, this surface 56 contacts thearcuate bearing surface 42 and draws the lug 43 outwardly from therecess 44. Further movement of the lever 52 raises the vsior to theposition shown in FIGURE 4.

I claim:

1. A helmet having a shell, a visor pivoted to said shell and capable ofpivoting movement between an upper open position and a lower closedposition to protect a wearer of said helmet, holder means carried bysaid shell for holding an electrically ignited cartridge, means carriedby said shell defining a chamber communicating with said holder means, apressure responsive member located within said chamber, and visorlowering mechanism connected to said pressure responsive member and tosaid visor, ignition of a cartridge in said holder means resulting in apressure increase in said chamber whereupon said member is moved andthereby causes said mechanism to lower said visor to said lower closedposition.

2. A helmet according to claim 1 in which said visor lowering mechanismincludes lost-motion means whereby said visor can be lowered manually.

3. A flying helmet having a shell, a visor pivoted to said shell andcapable of pivoting movement between an upper open position and a lowerclosed position to protect a wearer of said helmet, holder means carriedby said shell for holding an electrically ignited cartridge, pistonmeans and cooperating cylinder means and wherein interior of saidcylinder means communicates with said holder means and one of saidpiston means and said cylinder means is carried by said shell, and visorlowering mechanism connected to other of said piston means and saidcylinder means and connected to said visor, ignition of a cartridge insaid holder means resulting in a pressure increase in said cylindermeans whereupon said piston means is moved relatively to said cylindermeans and thereby causes said mechanism to lower said visor to saidlower closed position.

4. A flying helmet according to claim 3 in which said visor loweringmeans includes a resiliently acting member which resiliently transmitslowering movement to said visor.

5. A flying helmet according to claim 3 in which visor sidepieces arepivoted to said helmet shell in such a way that when said visor is insaid lowered position, said visor can be moved forwardly away from andrearwardly into contact with said shell, and in which said helmetincludes parts which cooperate with one another to prevent said visorbeing raised when in contact with said shell, and spring means whichbias said visor out of contact with said shell, said visor loweringmechanism operating to draw said visor rearwardly into contact with saidshell after having lowered said visor.

6. A flying helmet according to claim 5 in which a forwardly facingbearing surface having an arcuate profile is carried by said shell andin which a member is carried by one of said sidepieces and contacts saidbearing surface except when said visor is in said lowered position.

7. A flying helmet according to claim 6 including visor raisingmechanism and a lever controlling said visor raising mechanism,operation of said lever causing said visor to be drawn forwardly out ofcontact with said shell.

References Cited UNITED STATES PATENTS 3,001,199 9/1961 Williams et al.2-6 3,050,735 8/1962 Newman et a1. 2-6 3,123,831 3/1964 Wells et a1. 2-9XR 3,239,843 3/1966 Lobelle 2-6 3,345,642 10/1967 Uminski 2-6 3,383,7065/1968 Lobelle 2-6 JAMES R. BOLER, Primary Examiner US. Cl. X.R.128-1427

